do you ground your press?

[freonr22]

thank you Sky Diver!

[xrMike]

Lead styphnate (the primary explosive used in nearly all primers) is highly sensitive to static electricity. I used to work with/handle the stuff in a job years ago, and this was drilled into us constantly by management. My own research back then indicated that most industrial accidents involving it were attributable to a static discharge of some kind.

However, the fact that I've never heard any anecdotal evidence, or read any stories about primers blowing up on people (from static) makes me think there must be some good reason why that never seems to happen.

Maybe it's because the styphnate is inside a conductive metal cup which channels any current around it? I don't know...

It would be interesting to see that experiment performed on some primers.

[Sunwolf]

Make sure your ammo is grounded and your gunsafe for good measure!

[jmlivingston]

For you guys using mats, are they truly anti-static or are they static-dissipative?

I went through an exercise when I built my last data center and we were trying to determine exactly what type of flooring to spec out with the contractors. Apparently much of the anti-static stuff out there just prevents static build-up, so that if you're carrying a charge with you and walk onto the anti-static flooring it will carry with you until you touch something to discharge it. You just can't generate static when you walk across it. The flooring we eventually selected was static-dissipative. This flooring was connected to the main building ground and could actually absorb any charge your carry with you prior to stepping on it.

Do we have any commercial electricians out there who provide some input?

John

[Lancear15]

For you guys using mats, are they truly anti-static or are they static-dissipative?

I went through an exercise when I built my last data center and we were trying to determine exactly what type of flooring to spec out with the contractors. Apparently much of the anti-static stuff out there just prevents static build-up, so that if you're carrying a charge with you and walk onto the anti-static flooring it will carry with you until you touch something to discharge it. You just can't generate static when you walk across it. The flooring we eventually selected was static-dissipative. This flooring was connected to the main building ground and could actually absorb any charge your carry with you prior to stepping on it.

Do we have any commercial electricians out there who provide some input?

John

That's a question for an engineer. Electricians don't design, they just construct systems based on the engineers specs. Most electricians really have no idea how the systems they build actually even work. I'm an electrical superintendent for a union contractor and understand what your describing, but I have no experience with those types of mats.

Moot point anyhow since: http://www.ctmuzzleloaders.com/ctml_...ks/sparks.html

[xrMike]

Moot point anyhow since: http://www.ctmuzzleloaders.com/ctml_...ks/sparks.html

Moot for powders maybe, but like I said, I'd love to see that same experiment conducted on some primers. You have to consider them also.

[kmca]

Do you notice a difference in that the powder does not stick to the sides of the powder bottle once the press is grounded?

I ground my loaders, it's so easy to do. Doesn't help the powder sticking in the powder tube nearly as much as hanging a dryer sheet in there.

[ar15barrels]

Doesn't help the powder sticking in the powder tube nearly as much as hanging a dryer sheet in there.

Does your powder measure smell country fresh?
New or used dryer sheet?

[Revoman]

My initial thought for grounding was to simply stop the powder from migrating up the plastic bottle and hull. It's really tough to load good shotshells on a Santa Ana day. A static spark was secondary as I had also never heard of static igniting powder, although it did cross my mind that it might/could happen.

As stated, the mat seems to help, but there is still some powder that likes that migration thing regardless.

The experiment that has been shown by Sky_DiveR is really a good indication of what happens........or actually doesn't happen.

[Sky_DiveR]

Why does that always come up when someone mentions that they use a dryer sheet?

BTW: It does make my corn cob/walnut mix smell clean & fresh after a spring rain.

Seriously tho. I remember reading something about not using aluminum primer flip trays due to possibly igniting the primers.... or was that for plastic trays? I forget.

Dryer sheets are pretty handy... Controlling dust in the tumbler and powder sticking to plastic.

[jwest]

I do.
We've had this discussion before - maybe a search will yield some results.
What is even more important - digital scales should be used on an anti-static mat that is grounded as well.

[xrMike]

Another thing about that experiment posted above... That was performed on black powder, which none of us, or very few, are using.

We're using single-base (nitrocellulose) or double-base (nitrocellulose + nitroglycerin) smokeless powders.

You probably can't make any valid conclusions about the "sparkability" of smokeless powder if you run your test on black powder.

[ar15barrels]

Another thing about that experiment posted above... That was performed on black powder, which none of us, or very few, are using.

We're using single-base (nitrocellulose) or double-base (nitrocellulose + nitroglycerin) smokeless powders.

You probably can't make any valid conclusions about the "sparkability" of smokeless powder if you run your test on black powder.

If you read through the whole thing, you would also have seen the tests were run on smokeless powders too.

[7x57]

This is kind of fun.

The explanation given in the experiment is that BP is fairly conductive since it contains carbon. I think that's not the whole story. I seem to recall that the black appearance of modern BP is a carbon coating precisely to conduct electricity, and historically BP was greyish or brownish. Of course it wasn't called "black powder" either, just gunpowder.

The point is more theoretical than practical, but I think modern powders are engineered for this as a safety measure, contrary to what the article implies.

Now a critique of the above memories. The same is true of modern smokeless, the color is graphite-like for a reason. That leads to a question--why is coated SP greyish and coated BP black? Different coatings, or am I wrong about the BP being coated? Bullseye is much darker than 231, so it could just be different coatings I guess. It could also be the same thing but a different coating process--my guess is the somewhat reflective grey appearance requires pieces of smooth graphite sheet the size of a wavelength or more (let's say a micron) to get the reflective appearance. A coating process that produces smaller particles would probably give the black appearance with the same substance.

At least for smokeless another reason for the coating is friction--it protects against vibration and jostling grinding the grains and changing the burn rate over time. It would just truly suck if your slow rifle powder turned into pistol-rate powder because you've been carrying those shells for years on many hunting trips. Since I've never ever heard of shipping-related ka-booms, whatever they're doing is working. As far as BP goes, it's possible that the same is true but the grains appear to my eye to be so irregular that I'm not sure an anti-friction coating would help much. (Maybe that explains the appearance difference--there is no need to worry about friction?)

Again, all unreliable memory without looking it up.

ETA: I agree it's a pity the test wasn't done with primers. That said, notice that the metal cup and anvil function as an even better conductive coating. Since I've never heard of static-induced explosions from reloading, I suspect the primers may pass the test as well.

FWIW my little single-stage press has never been grounded, and no ka-booms yet.

7x57

[xrMike]

If you read through the whole thing, you would also have seen the tests were run on smokeless powders too.

Yeah, I missed that. He tested Unique also... My bad.